"This will give political parties enough time to run their campaigns," he told reporters, after a meeting with interim Prime Minister Surayud Chulanont.

Coalition government

Aspiring politicians now have around four months to prepare for the polls, reports the BBC's Jonathan Head from Bangkok.

Thai Rak Thai, Mr Thaksin's former party, has been renamed the People Power Party and appointed a veteran right-wing politician, Samak Sundaravej, to lead it into the election.

Top executives in the party have been barred from holding political office for five years, and Mr Thaksin remains in exile, but he retains strong popular support in the poor north and north-east of Thailand.

Even so, our correspondent adds, the party is unlikely to win enough votes for an outright majority.

There have been intense negotiations among Thailand's traditional political power-brokers in recent weeks to form other new parties for the election.

Many are local strongmen who have dominated their districts for decades and who joined Thai Rak Thai while Mr Thaksin was in office, but broke away after last year's coup.

The main party which opposed Mr Thaksin, the Democrats, has survived the last year intact, but its support has dwindled in recent years, and it is also unlikely to win a majority.

That means the next government will almost certainly be a coalition - and in the past, coalition governments in Thailand have acquired a reputation for being short-lived, and very corrupt, our correspondent says.